United States District Court Judge William Alsup is “tentatively” blaming poor maintenance of power lines as the cause of California’s deadly wildfires, not climate change.

Alsup made the ruling Thursday in a San Francisco federal court, NBC News reports. He was ruling on the actions of the Pacific Gas and Electric (PG&E) utility company in relation to a 2010 San Bruno gas pipeline inferno that killed several people.

Many have claimed climate change is the culprit for the raging wildfires.

“The Court tentatively finds that the single most recurring cause of the large 2017 and 2018 wildfires attributable to PG&E’s equipment has been the susceptibility of PG&E’s distribution lines to trees or limbs falling onto them during high-wind events,” the judge stated.

“The power conductors are almost always uninsulated,” Alsup wrote. “When the conductors are pushed together by falling trees or limbs, electrical sparks drop into the vegetation below. During the wildfire season when the vegetation is dry, these electrical sparks pose an extreme danger of igniting a wildfire.”

The wildfires have become a political phenomenon in the last two years, with climate change activists and California Gov. Jerry Brown blaming global warming for the blazes. PG&E itself has pointed to climate change as the cause of the wildfires.

The power company was quick to respond to the judge’s ruling with a statement reported by NBC.

“PG&E’s most important responsibility is the safety of our customers and the communities we serve,” the utility said. “We are aware of Judge Alsup’s latest order and are currently reviewing. We are committed to complying with all rules and regulations that apply to our work, while working together with our state and community partners and across all sectors and disciplines to develop comprehensive, long-term safety solutions for the future.”